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<FONT color="green">001</FONT>    package project3.lex;<a name="line.1"></a>
<FONT color="green">002</FONT>    <a name="line.2"></a>
<FONT color="green">003</FONT>    import project3.three.Node;<a name="line.3"></a>
<FONT color="green">004</FONT>    import project3.three.ParserException;<a name="line.4"></a>
<FONT color="green">005</FONT>    <a name="line.5"></a>
<FONT color="green">006</FONT>    /**<a name="line.6"></a>
<FONT color="green">007</FONT>     * A lexical analyzer produces a list of tokens.  This defines a token.<a name="line.7"></a>
<FONT color="green">008</FONT>     * A Token consists of a type, value, and lineNumber.  We inherit from<a name="line.8"></a>
<FONT color="green">009</FONT>     * &lt;b&gt;project3.Node&lt;/b&gt; so that we can add tokens to constant lists,<a name="line.9"></a>
<FONT color="green">010</FONT>     * attribute lists, or argument lists.<a name="line.10"></a>
<FONT color="green">011</FONT>     *<a name="line.11"></a>
<FONT color="green">012</FONT>     * &lt;p&gt;<a name="line.12"></a>
<FONT color="green">013</FONT>     * &lt;pre&gt;<a name="line.13"></a>
<FONT color="green">014</FONT>     * Domain:<a name="line.14"></a>
<FONT color="green">015</FONT>     *      type       : TokenType<a name="line.15"></a>
<FONT color="green">016</FONT>     *      value      : String<a name="line.16"></a>
<FONT color="green">017</FONT>     *      lineNumber : int<a name="line.17"></a>
<FONT color="green">018</FONT>     *<a name="line.18"></a>
<FONT color="green">019</FONT>     * Instance Invariant:<a name="line.19"></a>
<FONT color="green">020</FONT>     *      type &amp;ne; null AND<a name="line.20"></a>
<FONT color="green">021</FONT>     *      value &amp;ne; null AND<a name="line.21"></a>
<FONT color="green">022</FONT>     *      type = TokenType.EOF &amp;rArr; value = ""<a name="line.22"></a>
<FONT color="green">023</FONT>     * &lt;/pre&gt;<a name="line.23"></a>
<FONT color="green">024</FONT>     *<a name="line.24"></a>
<FONT color="green">025</FONT>     * Last Modified: 2 Mar 2006<a name="line.25"></a>
<FONT color="green">026</FONT>     * @author Scott N. Woodfield<a name="line.26"></a>
<FONT color="green">027</FONT>     * @version 1.0<a name="line.27"></a>
<FONT color="green">028</FONT>     * @see &lt;a href="../../srchtml/lex/Token.html"&gt;Source Code&lt;/a&gt;<a name="line.28"></a>
<FONT color="green">029</FONT>     */<a name="line.29"></a>
<FONT color="green">030</FONT>    public class Token <a name="line.30"></a>
<FONT color="green">031</FONT>        extends Node<a name="line.31"></a>
<FONT color="green">032</FONT>    {<a name="line.32"></a>
<FONT color="green">033</FONT>    //Constants<a name="line.33"></a>
<FONT color="green">034</FONT>    <a name="line.34"></a>
<FONT color="green">035</FONT>        /**<a name="line.35"></a>
<FONT color="green">036</FONT>         * The COMMA Token.  Used when we need a comma token but don't care about<a name="line.36"></a>
<FONT color="green">037</FONT>         * the line number.  This token is currently used in<a name="line.37"></a>
<FONT color="green">038</FONT>         * {@link project3.three.NamedList#getSeparator()<a name="line.38"></a>
<FONT color="green">039</FONT>         *      project3.three.NamedList.getSeparator()}<a name="line.39"></a>
<FONT color="green">040</FONT>         * and in<a name="line.40"></a>
<FONT color="green">041</FONT>         * {@link project3.PredicateList#getSeparator()<a name="line.41"></a>
<FONT color="green">042</FONT>         *      project3.PredeicateList.getSeparator()}. <a name="line.42"></a>
<FONT color="green">043</FONT>         * @see &lt;a href="../../srchtml/lex/Token.html#COMMA"&gt;Source Code&lt;/a&gt;<a name="line.43"></a>
<FONT color="green">044</FONT>         */<a name="line.44"></a>
<FONT color="green">045</FONT>        public static final Token COMMA = new Token(TokenType.COMMA, ",");<a name="line.45"></a>
<FONT color="green">046</FONT>    <a name="line.46"></a>
<FONT color="green">047</FONT>    //Domain Implementation<a name="line.47"></a>
<FONT color="green">048</FONT>        /**<a name="line.48"></a>
<FONT color="green">049</FONT>         * The type of the token. Accessed by "getTokenType".  It cannot be modified<a name="line.49"></a>
<FONT color="green">050</FONT>         * after the token has been created.<a name="line.50"></a>
<FONT color="green">051</FONT>         * @see &lt;a href="../../srchtml/lex/Token.html#type"&gt;Source Code&lt;/a&gt;<a name="line.51"></a>
<FONT color="green">052</FONT>         */<a name="line.52"></a>
<FONT color="green">053</FONT>        protected TokenType type  = TokenType.UNDEFINED;<a name="line.53"></a>
<FONT color="green">054</FONT>    <a name="line.54"></a>
<FONT color="green">055</FONT>        /**<a name="line.55"></a>
<FONT color="green">056</FONT>         * The value of the token.  The sequence of characters from the input stream<a name="line.56"></a>
<FONT color="green">057</FONT>         * that were parsed to create this token.  Some tokens with the same<a name="line.57"></a>
<FONT color="green">058</FONT>         * token type will always have the same value.  For instance, tokens of<a name="line.58"></a>
<FONT color="green">059</FONT>         * type TokenType.SEMICOLON will always have the value ";".  Other tokens,<a name="line.59"></a>
<FONT color="green">060</FONT>         * such as strings and identifiers can have different values.  Tokens of<a name="line.60"></a>
<FONT color="green">061</FONT>         * type EOF will have the "" or empty string value.<a name="line.61"></a>
<FONT color="green">062</FONT>         * @see &lt;a href="../../srchtml/lex/Token.html#value"&gt;Source Code&lt;/a&gt;<a name="line.62"></a>
<FONT color="green">063</FONT>         */<a name="line.63"></a>
<FONT color="green">064</FONT>        protected String    value = null;<a name="line.64"></a>
<FONT color="green">065</FONT>    <a name="line.65"></a>
<FONT color="green">066</FONT>        /**<a name="line.66"></a>
<FONT color="green">067</FONT>         * The line on which the first character of the token was found.<a name="line.67"></a>
<FONT color="green">068</FONT>         * @see &lt;a href="../../srchtml/lex/Token.html#lineNumber"&gt;Source Code&lt;/a&gt;<a name="line.68"></a>
<FONT color="green">069</FONT>         */<a name="line.69"></a>
<FONT color="green">070</FONT>        protected int    lineNumber = -1;<a name="line.70"></a>
<FONT color="green">071</FONT>    <a name="line.71"></a>
<FONT color="green">072</FONT>    //Constructors<a name="line.72"></a>
<FONT color="green">073</FONT>        /**<a name="line.73"></a>
<FONT color="green">074</FONT>         * Constructs a token from a type and value.  Used primarily to create<a name="line.74"></a>
<FONT color="green">075</FONT>         * constants.<a name="line.75"></a>
<FONT color="green">076</FONT>         *<a name="line.76"></a>
<FONT color="green">077</FONT>         * &lt;p&gt;<a name="line.77"></a>
<FONT color="green">078</FONT>         * &lt;table&gt;<a name="line.78"></a>
<FONT color="green">079</FONT>         *   &lt;tr&gt;<a name="line.79"></a>
<FONT color="green">080</FONT>         *     &lt;td&gt; &lt;b&gt;Precondition&lt;/b&gt;: &lt;/td&gt;<a name="line.80"></a>
<FONT color="green">081</FONT>         *     &lt;td&gt; None&lt;/td&gt;<a name="line.81"></a>
<FONT color="green">082</FONT>         *   &lt;/tr&gt;<a name="line.82"></a>
<FONT color="green">083</FONT>         *   &lt;tr&gt;<a name="line.83"></a>
<FONT color="green">084</FONT>         *     &lt;td valign=top&gt;<a name="line.84"></a>
<FONT color="green">085</FONT>         *       &lt;b&gt;PostCondition&lt;/b&gt;:<a name="line.85"></a>
<FONT color="green">086</FONT>         *     &lt;/td&gt;<a name="line.86"></a>
<FONT color="green">087</FONT>         *     &lt;td valign=top&gt; <a name="line.87"></a>
<FONT color="green">088</FONT>         *       this.type = type&lt;br/&gt;<a name="line.88"></a>
<FONT color="green">089</FONT>         *       this.type = TokenType.EOF &amp;rArr; this.value = ""&lt;br/&gt;<a name="line.89"></a>
<FONT color="green">090</FONT>         *       this.type &amp;ne; TokenType.EOF &amp;rArr; this.value = value&lt;br/&gt;<a name="line.90"></a>
<FONT color="green">091</FONT>         *       this.lineNumber = -1<a name="line.91"></a>
<FONT color="green">092</FONT>         *     &lt;/td&gt;<a name="line.92"></a>
<FONT color="green">093</FONT>         *     &lt;td valign=top&gt;<a name="line.93"></a>
<FONT color="green">094</FONT>         *       AND &lt;br/&gt;<a name="line.94"></a>
<FONT color="green">095</FONT>         *       AND &lt;br/&gt;<a name="line.95"></a>
<FONT color="green">096</FONT>         *       AND &lt;br/&gt;<a name="line.96"></a>
<FONT color="green">097</FONT>         *       &amp;nbsp;<a name="line.97"></a>
<FONT color="green">098</FONT>         *     &lt;/td&gt;<a name="line.98"></a>
<FONT color="green">099</FONT>         *   &lt;/tr&gt;<a name="line.99"></a>
<FONT color="green">100</FONT>         * &lt;/table&gt;<a name="line.100"></a>
<FONT color="green">101</FONT>         * @param type the type of the token.  <a name="line.101"></a>
<FONT color="green">102</FONT>         * @param value the value of the token.<a name="line.102"></a>
<FONT color="green">103</FONT>         * @see &lt;a href="../../srchtml/lex/Token.html#StdConstructor"&gt;Source Code&lt;/a&gt;<a name="line.103"></a>
<FONT color="green">104</FONT>         */<a name="line.104"></a>
<FONT color="green">105</FONT>        private Token(TokenType type, String value)<a name="line.105"></a>
<FONT color="green">106</FONT>        {<a name="line.106"></a>
<FONT color="green">107</FONT>            this.type = type;<a name="line.107"></a>
<FONT color="green">108</FONT>            if(type == TokenType.EOF){<a name="line.108"></a>
<FONT color="green">109</FONT>               this.value = "";<a name="line.109"></a>
<FONT color="green">110</FONT>            } else {<a name="line.110"></a>
<FONT color="green">111</FONT>               this.value = value;<a name="line.111"></a>
<FONT color="green">112</FONT>            };<a name="line.112"></a>
<FONT color="green">113</FONT>    <a name="line.113"></a>
<FONT color="green">114</FONT>            this.lineNumber = -1;<a name="line.114"></a>
<FONT color="green">115</FONT>        }<a name="line.115"></a>
<FONT color="green">116</FONT>    <a name="line.116"></a>
<FONT color="green">117</FONT>        /**<a name="line.117"></a>
<FONT color="green">118</FONT>         * Constructs a token from a type, value, and lineNumber.<a name="line.118"></a>
<FONT color="green">119</FONT>         *<a name="line.119"></a>
<FONT color="green">120</FONT>         * &lt;p&gt;<a name="line.120"></a>
<FONT color="green">121</FONT>         * &lt;table&gt;<a name="line.121"></a>
<FONT color="green">122</FONT>         *   &lt;tr&gt;<a name="line.122"></a>
<FONT color="green">123</FONT>         *     &lt;td valign=top&gt;<a name="line.123"></a>
<FONT color="green">124</FONT>         *         &lt;b&gt;Precondition&lt;/b&gt;:<a name="line.124"></a>
<FONT color="green">125</FONT>         *     &lt;/td&gt;<a name="line.125"></a>
<FONT color="green">126</FONT>         *     &lt;td valign=top&gt;<a name="line.126"></a>
<FONT color="green">127</FONT>         *       checkConstructorPrecondition()<a name="line.127"></a>
<FONT color="green">128</FONT>         *     &lt;/td&gt;<a name="line.128"></a>
<FONT color="green">129</FONT>         *     &lt;td&gt;<a name="line.129"></a>
<FONT color="green">130</FONT>         *     &lt;/td&gt;<a name="line.130"></a>
<FONT color="green">131</FONT>         *   &lt;/tr&gt;<a name="line.131"></a>
<FONT color="green">132</FONT>         *   &lt;tr&gt;<a name="line.132"></a>
<FONT color="green">133</FONT>         *     &lt;td valign=top&gt;<a name="line.133"></a>
<FONT color="green">134</FONT>         *         &lt;b&gt;PostCondition&lt;/b&gt;:<a name="line.134"></a>
<FONT color="green">135</FONT>         *     &lt;/td&gt;<a name="line.135"></a>
<FONT color="green">136</FONT>         *     &lt;td valign=top&gt;<a name="line.136"></a>
<FONT color="green">137</FONT>         *       this.type = type &lt;br/&gt;<a name="line.137"></a>
<FONT color="green">138</FONT>         *       this.type = TokenType.EOF &amp;rArr; this.value = "" &lt;br/&gt;<a name="line.138"></a>
<FONT color="green">139</FONT>         *       this.type &amp;ne; TokenType.EOF &amp;rArr; this.value = value &lt;br/&gt;<a name="line.139"></a>
<FONT color="green">140</FONT>         *       this.lineNumber = lineNumber<a name="line.140"></a>
<FONT color="green">141</FONT>         *     &lt;/td&gt;<a name="line.141"></a>
<FONT color="green">142</FONT>         *     &lt;td valign=top&gt;<a name="line.142"></a>
<FONT color="green">143</FONT>         *       AND&lt;br/&gt;<a name="line.143"></a>
<FONT color="green">144</FONT>         *       AND&lt;br/&gt;<a name="line.144"></a>
<FONT color="green">145</FONT>         *       AND&lt;br/&gt;<a name="line.145"></a>
<FONT color="green">146</FONT>         *       &amp;nbsp;<a name="line.146"></a>
<FONT color="green">147</FONT>         *     &lt;/td&gt;<a name="line.147"></a>
<FONT color="green">148</FONT>         *   &lt;/tr&gt;<a name="line.148"></a>
<FONT color="green">149</FONT>         * &lt;/table&gt;<a name="line.149"></a>
<FONT color="green">150</FONT>         *<a name="line.150"></a>
<FONT color="green">151</FONT>         * @param type the type of the token.  <a name="line.151"></a>
<FONT color="green">152</FONT>         * @param value the value of the token.<a name="line.152"></a>
<FONT color="green">153</FONT>         * @param lineNumber the lineNumber of the token.<a name="line.153"></a>
<FONT color="green">154</FONT>         *<a name="line.154"></a>
<FONT color="green">155</FONT>         * @throws ParserException<a name="line.155"></a>
<FONT color="green">156</FONT>         * @see &lt;a href="../../srchtml/lex/Token.html#StdConstructor2"&gt;Source Code&lt;/a&gt;<a name="line.156"></a>
<FONT color="green">157</FONT>         */<a name="line.157"></a>
<FONT color="green">158</FONT>        public Token(TokenType type, String value, int lineNumber)<a name="line.158"></a>
<FONT color="green">159</FONT>            throws ParserException <a name="line.159"></a>
<FONT color="green">160</FONT>        {<a name="line.160"></a>
<FONT color="green">161</FONT>            checkConstructorPrecondition(type, value, lineNumber);<a name="line.161"></a>
<FONT color="green">162</FONT>    <a name="line.162"></a>
<FONT color="green">163</FONT>            this.type = type;<a name="line.163"></a>
<FONT color="green">164</FONT>            if(type == TokenType.EOF){<a name="line.164"></a>
<FONT color="green">165</FONT>               this.value = "";<a name="line.165"></a>
<FONT color="green">166</FONT>            } else {<a name="line.166"></a>
<FONT color="green">167</FONT>               this.value = value;<a name="line.167"></a>
<FONT color="green">168</FONT>            };<a name="line.168"></a>
<FONT color="green">169</FONT>    <a name="line.169"></a>
<FONT color="green">170</FONT>            this.lineNumber = lineNumber;<a name="line.170"></a>
<FONT color="green">171</FONT>        }<a name="line.171"></a>
<FONT color="green">172</FONT>    <a name="line.172"></a>
<FONT color="green">173</FONT>        /**<a name="line.173"></a>
<FONT color="green">174</FONT>         * The copy constructor.<a name="line.174"></a>
<FONT color="green">175</FONT>         *<a name="line.175"></a>
<FONT color="green">176</FONT>         * &lt;p&gt;<a name="line.176"></a>
<FONT color="green">177</FONT>         * &lt;table&gt;<a name="line.177"></a>
<FONT color="green">178</FONT>         *   &lt;tr&gt;<a name="line.178"></a>
<FONT color="green">179</FONT>         *     &lt;td valign=top&gt;<a name="line.179"></a>
<FONT color="green">180</FONT>         *         &lt;b&gt;Precondition&lt;/b&gt;:<a name="line.180"></a>
<FONT color="green">181</FONT>         *     &lt;/td&gt;<a name="line.181"></a>
<FONT color="green">182</FONT>         *     &lt;td valign=top&gt;<a name="line.182"></a>
<FONT color="green">183</FONT>         *         token &amp;ne; null<a name="line.183"></a>
<FONT color="green">184</FONT>         *     &lt;/td&gt;<a name="line.184"></a>
<FONT color="green">185</FONT>         *     &lt;td valign=top&gt;<a name="line.185"></a>
<FONT color="green">186</FONT>         *     &lt;/td&gt;<a name="line.186"></a>
<FONT color="green">187</FONT>         *   &lt;/tr&gt;<a name="line.187"></a>
<FONT color="green">188</FONT>         *   &lt;tr&gt;<a name="line.188"></a>
<FONT color="green">189</FONT>         *     &lt;td valign=top&gt;<a name="line.189"></a>
<FONT color="green">190</FONT>         *         &lt;b&gt;PostCondition&lt;/b&gt;:<a name="line.190"></a>
<FONT color="green">191</FONT>         *     &lt;/td&gt;<a name="line.191"></a>
<FONT color="green">192</FONT>         *     &lt;td valign=top&gt;<a name="line.192"></a>
<FONT color="green">193</FONT>         *       type = token.type &lt;br/&gt;<a name="line.193"></a>
<FONT color="green">194</FONT>         *       value = new String(token.value)&lt;br/&gt;<a name="line.194"></a>
<FONT color="green">195</FONT>         *       lineNumber = token.lineNumber<a name="line.195"></a>
<FONT color="green">196</FONT>         *     &lt;/td&gt;<a name="line.196"></a>
<FONT color="green">197</FONT>         *     &lt;td valign=top&gt;<a name="line.197"></a>
<FONT color="green">198</FONT>         *       AND&lt;br/&gt;<a name="line.198"></a>
<FONT color="green">199</FONT>         *       AND&lt;br/&gt;<a name="line.199"></a>
<FONT color="green">200</FONT>         *       &amp;nbsp;<a name="line.200"></a>
<FONT color="green">201</FONT>         *     &lt;/td&gt;<a name="line.201"></a>
<FONT color="green">202</FONT>         *   &lt;/tr&gt;<a name="line.202"></a>
<FONT color="green">203</FONT>         * &lt;/table&gt;<a name="line.203"></a>
<FONT color="green">204</FONT>         *<a name="line.204"></a>
<FONT color="green">205</FONT>         * @param token the token to copy.<a name="line.205"></a>
<FONT color="green">206</FONT>         * @see &lt;a href="../../srchtml/lex/Token.html#CopyConstructor"&gt;Source Code&lt;/a&gt;<a name="line.206"></a>
<FONT color="green">207</FONT>         */<a name="line.207"></a>
<FONT color="green">208</FONT>        public Token(Token token)<a name="line.208"></a>
<FONT color="green">209</FONT>        {<a name="line.209"></a>
<FONT color="green">210</FONT>            assert token != null;<a name="line.210"></a>
<FONT color="green">211</FONT>    <a name="line.211"></a>
<FONT color="green">212</FONT>            type = token.type;<a name="line.212"></a>
<FONT color="green">213</FONT>            value = token.value == null ? null : new String(token.value);<a name="line.213"></a>
<FONT color="green">214</FONT>            lineNumber = token.lineNumber;<a name="line.214"></a>
<FONT color="green">215</FONT>        }<a name="line.215"></a>
<FONT color="green">216</FONT>    <a name="line.216"></a>
<FONT color="green">217</FONT>    //Queries<a name="line.217"></a>
<FONT color="green">218</FONT>        /**<a name="line.218"></a>
<FONT color="green">219</FONT>         *Compares two Tokens to see if they are equal. Notice that we only use<a name="line.219"></a>
<FONT color="green">220</FONT>         * the type and value to determine if two tokens are equal. We ignore the<a name="line.220"></a>
<FONT color="green">221</FONT>         * line number.<a name="line.221"></a>
<FONT color="green">222</FONT>         *<a name="line.222"></a>
<FONT color="green">223</FONT>         * &lt;p&gt;<a name="line.223"></a>
<FONT color="green">224</FONT>         * &lt;table&gt;<a name="line.224"></a>
<FONT color="green">225</FONT>         *   &lt;tr&gt;<a name="line.225"></a>
<FONT color="green">226</FONT>         *     &lt;td valign=top&gt;<a name="line.226"></a>
<FONT color="green">227</FONT>         *       &lt;b&gt;Precondition&lt;/b&gt;:<a name="line.227"></a>
<FONT color="green">228</FONT>         *     &lt;/td&gt;<a name="line.228"></a>
<FONT color="green">229</FONT>         *     &lt;td valign=top&gt;<a name="line.229"></a>
<FONT color="green">230</FONT>         *       none<a name="line.230"></a>
<FONT color="green">231</FONT>         *     &lt;/td&gt;<a name="line.231"></a>
<FONT color="green">232</FONT>         *     &lt;td valign=top&gt;<a name="line.232"></a>
<FONT color="green">233</FONT>         *     &lt;/td&gt;<a name="line.233"></a>
<FONT color="green">234</FONT>         *   &lt;/tr&gt;<a name="line.234"></a>
<FONT color="green">235</FONT>         *   &lt;tr&gt;<a name="line.235"></a>
<FONT color="green">236</FONT>         *     &lt;td valign=top&gt;<a name="line.236"></a>
<FONT color="green">237</FONT>         *       &lt;b&gt;PostCondition&lt;/b&gt;:<a name="line.237"></a>
<FONT color="green">238</FONT>         *     &lt;/td&gt;<a name="line.238"></a>
<FONT color="green">239</FONT>         *     &lt;td valign=top&gt;<a name="line.239"></a>
<FONT color="green">240</FONT>         *       result = object &amp;ne; null &lt;br/&gt;<a name="line.240"></a>
<FONT color="green">241</FONT>         *       object &lt;i&gt;instanceof&lt;/i&gt; Token &lt;br/&gt;<a name="line.241"></a>
<FONT color="green">242</FONT>         *       type = object.type &lt;br/&gt;<a name="line.242"></a>
<FONT color="green">243</FONT>         *       value = object.value <a name="line.243"></a>
<FONT color="green">244</FONT>         *     &lt;/td&gt;<a name="line.244"></a>
<FONT color="green">245</FONT>         *     &lt;td valign=top&gt;<a name="line.245"></a>
<FONT color="green">246</FONT>         *       AND&lt;br/&gt;<a name="line.246"></a>
<FONT color="green">247</FONT>         *       AND&lt;br/&gt;<a name="line.247"></a>
<FONT color="green">248</FONT>         *       AND&lt;br/&gt;<a name="line.248"></a>
<FONT color="green">249</FONT>         *       &amp;nbsp;<a name="line.249"></a>
<FONT color="green">250</FONT>         *     &lt;/td&gt;<a name="line.250"></a>
<FONT color="green">251</FONT>         *   &lt;/tr&gt;<a name="line.251"></a>
<FONT color="green">252</FONT>         * &lt;/table&gt;<a name="line.252"></a>
<FONT color="green">253</FONT>         *<a name="line.253"></a>
<FONT color="green">254</FONT>         * @param object the object we are comparing this to<a name="line.254"></a>
<FONT color="green">255</FONT>         *<a name="line.255"></a>
<FONT color="green">256</FONT>         * @return true iff the objects are equal<a name="line.256"></a>
<FONT color="green">257</FONT>         * @see &lt;a href="../../srchtml/lex/Token.html#equals"&gt;Source Code&lt;/a&gt;<a name="line.257"></a>
<FONT color="green">258</FONT>         */<a name="line.258"></a>
<FONT color="green">259</FONT>        public boolean equals(Object object)<a name="line.259"></a>
<FONT color="green">260</FONT>        {<a name="line.260"></a>
<FONT color="green">261</FONT>            boolean result = object != null &amp;&amp; object instanceof Token;<a name="line.261"></a>
<FONT color="green">262</FONT>            if(result){<a name="line.262"></a>
<FONT color="green">263</FONT>                Token token = (Token)object;<a name="line.263"></a>
<FONT color="green">264</FONT>                result = type == token.type &amp;&amp;<a name="line.264"></a>
<FONT color="green">265</FONT>                         ((value ==  null &amp;&amp; token.value == null) ||<a name="line.265"></a>
<FONT color="green">266</FONT>                          (value != null &amp;&amp; value.equals(token.value))<a name="line.266"></a>
<FONT color="green">267</FONT>                         );<a name="line.267"></a>
<FONT color="green">268</FONT>            };<a name="line.268"></a>
<FONT color="green">269</FONT>            return result;<a name="line.269"></a>
<FONT color="green">270</FONT>        }<a name="line.270"></a>
<FONT color="green">271</FONT>    <a name="line.271"></a>
<FONT color="green">272</FONT>        /**<a name="line.272"></a>
<FONT color="green">273</FONT>         * The getter method for type.<a name="line.273"></a>
<FONT color="green">274</FONT>         * <a name="line.274"></a>
<FONT color="green">275</FONT>         * &lt;p&gt;<a name="line.275"></a>
<FONT color="green">276</FONT>         * &lt;table&gt;<a name="line.276"></a>
<FONT color="green">277</FONT>         *   &lt;tr&gt;<a name="line.277"></a>
<FONT color="green">278</FONT>         *     &lt;td valign=top&gt;<a name="line.278"></a>
<FONT color="green">279</FONT>         *       &lt;b&gt;Precondition&lt;/b&gt;:<a name="line.279"></a>
<FONT color="green">280</FONT>         *     &lt;/td&gt;<a name="line.280"></a>
<FONT color="green">281</FONT>         *     &lt;td valign=top&gt;<a name="line.281"></a>
<FONT color="green">282</FONT>         *       none<a name="line.282"></a>
<FONT color="green">283</FONT>         *     &lt;/td&gt;<a name="line.283"></a>
<FONT color="green">284</FONT>         *     &lt;td valign=top&gt;<a name="line.284"></a>
<FONT color="green">285</FONT>         *     &lt;/td&gt;<a name="line.285"></a>
<FONT color="green">286</FONT>         *   &lt;/tr&gt;<a name="line.286"></a>
<FONT color="green">287</FONT>         *   &lt;tr&gt;<a name="line.287"></a>
<FONT color="green">288</FONT>         *     &lt;td valign=top&gt;<a name="line.288"></a>
<FONT color="green">289</FONT>         *       &lt;b&gt;PostCondition&lt;/b&gt;:<a name="line.289"></a>
<FONT color="green">290</FONT>         *     &lt;/td&gt;<a name="line.290"></a>
<FONT color="green">291</FONT>         *     &lt;td valign=top&gt;<a name="line.291"></a>
<FONT color="green">292</FONT>         *       result = type<a name="line.292"></a>
<FONT color="green">293</FONT>         *     &lt;/td&gt;<a name="line.293"></a>
<FONT color="green">294</FONT>         *     &lt;td valign=top&gt;<a name="line.294"></a>
<FONT color="green">295</FONT>         *     &lt;/td&gt;<a name="line.295"></a>
<FONT color="green">296</FONT>         *   &lt;/tr&gt;<a name="line.296"></a>
<FONT color="green">297</FONT>         * &lt;/table&gt;<a name="line.297"></a>
<FONT color="green">298</FONT>         *<a name="line.298"></a>
<FONT color="green">299</FONT>         * @return the type<a name="line.299"></a>
<FONT color="green">300</FONT>         * @see &lt;a href="../../srchtml/lex/Token.html#getTokenType"&gt;Source Code&lt;/a&gt;<a name="line.300"></a>
<FONT color="green">301</FONT>         */<a name="line.301"></a>
<FONT color="green">302</FONT>        public TokenType getTokenType()<a name="line.302"></a>
<FONT color="green">303</FONT>        {<a name="line.303"></a>
<FONT color="green">304</FONT>            return type;<a name="line.304"></a>
<FONT color="green">305</FONT>        }<a name="line.305"></a>
<FONT color="green">306</FONT>    <a name="line.306"></a>
<FONT color="green">307</FONT>        /**<a name="line.307"></a>
<FONT color="green">308</FONT>         * The getter method for value.<a name="line.308"></a>
<FONT color="green">309</FONT>         * <a name="line.309"></a>
<FONT color="green">310</FONT>         * &lt;p&gt;<a name="line.310"></a>
<FONT color="green">311</FONT>         * &lt;table&gt;<a name="line.311"></a>
<FONT color="green">312</FONT>         *   &lt;tr&gt;<a name="line.312"></a>
<FONT color="green">313</FONT>         *     &lt;td valign=top&gt;<a name="line.313"></a>
<FONT color="green">314</FONT>         *       &lt;b&gt;Precondition&lt;/b&gt;:<a name="line.314"></a>
<FONT color="green">315</FONT>         *     &lt;/td&gt;<a name="line.315"></a>
<FONT color="green">316</FONT>         *     &lt;td valign=top&gt;<a name="line.316"></a>
<FONT color="green">317</FONT>         *       none<a name="line.317"></a>
<FONT color="green">318</FONT>         *     &lt;/td&gt;<a name="line.318"></a>
<FONT color="green">319</FONT>         *     &lt;td valign=top&gt;<a name="line.319"></a>
<FONT color="green">320</FONT>         *     &lt;/td&gt;<a name="line.320"></a>
<FONT color="green">321</FONT>         *   &lt;/tr&gt;<a name="line.321"></a>
<FONT color="green">322</FONT>         *   &lt;tr&gt;<a name="line.322"></a>
<FONT color="green">323</FONT>         *     &lt;td valign=top&gt;<a name="line.323"></a>
<FONT color="green">324</FONT>         *       &lt;b&gt;PostCondition&lt;/b&gt;:<a name="line.324"></a>
<FONT color="green">325</FONT>         *     &lt;/td&gt;<a name="line.325"></a>
<FONT color="green">326</FONT>         *     &lt;td valign=top&gt;<a name="line.326"></a>
<FONT color="green">327</FONT>         *       type = TokenType.STRING &amp;rArr; result = "'" + value + "'" &lt;br/&gt;<a name="line.327"></a>
<FONT color="green">328</FONT>         *       type &amp;ne; STRING &amp;rArr; result = value<a name="line.328"></a>
<FONT color="green">329</FONT>         *     &lt;/td&gt;<a name="line.329"></a>
<FONT color="green">330</FONT>         *     &lt;td valign=top&gt;<a name="line.330"></a>
<FONT color="green">331</FONT>         *       AND&lt;br/&gt;<a name="line.331"></a>
<FONT color="green">332</FONT>         *       &amp;nbsp<a name="line.332"></a>
<FONT color="green">333</FONT>         *     &lt;/td&gt;<a name="line.333"></a>
<FONT color="green">334</FONT>         *   &lt;/tr&gt;<a name="line.334"></a>
<FONT color="green">335</FONT>         * &lt;/table&gt;<a name="line.335"></a>
<FONT color="green">336</FONT>         *<a name="line.336"></a>
<FONT color="green">337</FONT>         * @return the value<a name="line.337"></a>
<FONT color="green">338</FONT>         * @see &lt;a href="../../srchtml/lex/Token.html#getValue"&gt;Source Code&lt;/a&gt;<a name="line.338"></a>
<FONT color="green">339</FONT>         */<a name="line.339"></a>
<FONT color="green">340</FONT>        public String getValue()<a name="line.340"></a>
<FONT color="green">341</FONT>        {<a name="line.341"></a>
<FONT color="green">342</FONT>            String result = null;<a name="line.342"></a>
<FONT color="green">343</FONT>            if(type == TokenType.STRING){<a name="line.343"></a>
<FONT color="green">344</FONT>                 result = '\'' + value + '\'';<a name="line.344"></a>
<FONT color="green">345</FONT>            } else {<a name="line.345"></a>
<FONT color="green">346</FONT>                 result = value;<a name="line.346"></a>
<FONT color="green">347</FONT>            };<a name="line.347"></a>
<FONT color="green">348</FONT>            return result;<a name="line.348"></a>
<FONT color="green">349</FONT>        }<a name="line.349"></a>
<FONT color="green">350</FONT>    <a name="line.350"></a>
<FONT color="green">351</FONT>        /**<a name="line.351"></a>
<FONT color="green">352</FONT>         * The getter method for lineNumber.<a name="line.352"></a>
<FONT color="green">353</FONT>         * <a name="line.353"></a>
<FONT color="green">354</FONT>         * &lt;p&gt;<a name="line.354"></a>
<FONT color="green">355</FONT>         * &lt;table&gt;<a name="line.355"></a>
<FONT color="green">356</FONT>         *   &lt;tr&gt;<a name="line.356"></a>
<FONT color="green">357</FONT>         *     &lt;td valign=top&gt;<a name="line.357"></a>
<FONT color="green">358</FONT>         *       &lt;b&gt;Precondition&lt;/b&gt;:<a name="line.358"></a>
<FONT color="green">359</FONT>         *     &lt;/td&gt;<a name="line.359"></a>
<FONT color="green">360</FONT>         *     &lt;td valign=top&gt;<a name="line.360"></a>
<FONT color="green">361</FONT>         *       none<a name="line.361"></a>
<FONT color="green">362</FONT>         *     &lt;/td&gt;<a name="line.362"></a>
<FONT color="green">363</FONT>         *     &lt;td valign=top&gt;<a name="line.363"></a>
<FONT color="green">364</FONT>         *     &lt;/td&gt;<a name="line.364"></a>
<FONT color="green">365</FONT>         *   &lt;/tr&gt;<a name="line.365"></a>
<FONT color="green">366</FONT>         *   &lt;tr&gt;<a name="line.366"></a>
<FONT color="green">367</FONT>         *     &lt;td valign=top&gt;<a name="line.367"></a>
<FONT color="green">368</FONT>         *       &lt;b&gt;PostCondition&lt;/b&gt;:<a name="line.368"></a>
<FONT color="green">369</FONT>         *     &lt;/td&gt;<a name="line.369"></a>
<FONT color="green">370</FONT>         *     &lt;td valign=top&gt;<a name="line.370"></a>
<FONT color="green">371</FONT>         *       result = lineNumber<a name="line.371"></a>
<FONT color="green">372</FONT>         *     &lt;/td&gt;<a name="line.372"></a>
<FONT color="green">373</FONT>         *     &lt;td valign=top&gt;<a name="line.373"></a>
<FONT color="green">374</FONT>         *     &lt;/td&gt;<a name="line.374"></a>
<FONT color="green">375</FONT>         *   &lt;/tr&gt;<a name="line.375"></a>
<FONT color="green">376</FONT>         * &lt;/table&gt;<a name="line.376"></a>
<FONT color="green">377</FONT>         *<a name="line.377"></a>
<FONT color="green">378</FONT>         * @return the lineNumber<a name="line.378"></a>
<FONT color="green">379</FONT>         * @see &lt;a href="../../srchtml/lex/Token.html#getLineNumber"&gt;Source Code&lt;/a&gt;<a name="line.379"></a>
<FONT color="green">380</FONT>         */<a name="line.380"></a>
<FONT color="green">381</FONT>        public int getLineNumber()<a name="line.381"></a>
<FONT color="green">382</FONT>        {<a name="line.382"></a>
<FONT color="green">383</FONT>            return lineNumber;<a name="line.383"></a>
<FONT color="green">384</FONT>        }<a name="line.384"></a>
<FONT color="green">385</FONT>    <a name="line.385"></a>
<FONT color="green">386</FONT>        /**<a name="line.386"></a>
<FONT color="green">387</FONT>         * Returns the string value of this token.<a name="line.387"></a>
<FONT color="green">388</FONT>         *<a name="line.388"></a>
<FONT color="green">389</FONT>         * &lt;p&gt;<a name="line.389"></a>
<FONT color="green">390</FONT>         * &lt;table&gt;<a name="line.390"></a>
<FONT color="green">391</FONT>         *   &lt;tr&gt;<a name="line.391"></a>
<FONT color="green">392</FONT>         *     &lt;td valign=top&gt;<a name="line.392"></a>
<FONT color="green">393</FONT>         *       &lt;b&gt;Precondition&lt;/b&gt;:<a name="line.393"></a>
<FONT color="green">394</FONT>         *     &lt;/td&gt;<a name="line.394"></a>
<FONT color="green">395</FONT>         *     &lt;td valign=top&gt;<a name="line.395"></a>
<FONT color="green">396</FONT>         *       none<a name="line.396"></a>
<FONT color="green">397</FONT>         *     &lt;/td&gt;<a name="line.397"></a>
<FONT color="green">398</FONT>         *     &lt;td valign=top&gt;<a name="line.398"></a>
<FONT color="green">399</FONT>         *     &lt;/td&gt;<a name="line.399"></a>
<FONT color="green">400</FONT>         *   &lt;/tr&gt;<a name="line.400"></a>
<FONT color="green">401</FONT>         *   &lt;tr&gt;<a name="line.401"></a>
<FONT color="green">402</FONT>         *     &lt;td valign=top&gt;<a name="line.402"></a>
<FONT color="green">403</FONT>         *       &lt;b&gt;Postcondition&lt;/b&gt;:<a name="line.403"></a>
<FONT color="green">404</FONT>         *     &lt;/td&gt;<a name="line.404"></a>
<FONT color="green">405</FONT>         *     &lt;td valign=top&gt;<a name="line.405"></a>
<FONT color="green">406</FONT>         *       result = "(" + type + ", \"" + value + ", \")" + lineNumber + ")"<a name="line.406"></a>
<FONT color="green">407</FONT>         *     &lt;/td&gt;<a name="line.407"></a>
<FONT color="green">408</FONT>         *     &lt;td valign=top&gt;<a name="line.408"></a>
<FONT color="green">409</FONT>         *     &lt;/td&gt;<a name="line.409"></a>
<FONT color="green">410</FONT>         *   &lt;/tr&gt;<a name="line.410"></a>
<FONT color="green">411</FONT>         * &lt;/table&gt;<a name="line.411"></a>
<FONT color="green">412</FONT>         *<a name="line.412"></a>
<FONT color="green">413</FONT>         * @return a string representing this token<a name="line.413"></a>
<FONT color="green">414</FONT>         * @see &lt;a href="../../srchtml/lex/Token.html#toString"&gt;Source Code&lt;/a&gt;<a name="line.414"></a>
<FONT color="green">415</FONT>         */<a name="line.415"></a>
<FONT color="green">416</FONT>        public String toString()<a name="line.416"></a>
<FONT color="green">417</FONT>        {<a name="line.417"></a>
<FONT color="green">418</FONT>            StringBuffer result = new StringBuffer();<a name="line.418"></a>
<FONT color="green">419</FONT>            result.append("(");<a name="line.419"></a>
<FONT color="green">420</FONT>            result.append(type);<a name="line.420"></a>
<FONT color="green">421</FONT>            result.append(", ");<a name="line.421"></a>
<FONT color="green">422</FONT>            result.append(value);<a name="line.422"></a>
<FONT color="green">423</FONT>            result.append(", ");<a name="line.423"></a>
<FONT color="green">424</FONT>            result.append(lineNumber);<a name="line.424"></a>
<FONT color="green">425</FONT>            result.append(")");<a name="line.425"></a>
<FONT color="green">426</FONT>            return value;<a name="line.426"></a>
<FONT color="green">427</FONT>        }<a name="line.427"></a>
<FONT color="green">428</FONT>    <a name="line.428"></a>
<FONT color="green">429</FONT>        /**<a name="line.429"></a>
<FONT color="green">430</FONT>         * The hash value for a token.<a name="line.430"></a>
<FONT color="green">431</FONT>         * <a name="line.431"></a>
<FONT color="green">432</FONT>         * &lt;p&gt;<a name="line.432"></a>
<FONT color="green">433</FONT>         * &lt;table&gt;<a name="line.433"></a>
<FONT color="green">434</FONT>         *   &lt;tr&gt;<a name="line.434"></a>
<FONT color="green">435</FONT>         *     &lt;td valign=top&gt;<a name="line.435"></a>
<FONT color="green">436</FONT>         *       &lt;b&gt;Precondition&lt;/b&gt;:<a name="line.436"></a>
<FONT color="green">437</FONT>         *     &lt;/td&gt;<a name="line.437"></a>
<FONT color="green">438</FONT>         *     &lt;td valign=top&gt;<a name="line.438"></a>
<FONT color="green">439</FONT>         *       none<a name="line.439"></a>
<FONT color="green">440</FONT>         *     &lt;/td&gt;<a name="line.440"></a>
<FONT color="green">441</FONT>         *     &lt;td valign=top&gt;<a name="line.441"></a>
<FONT color="green">442</FONT>         *     &lt;/td&gt;<a name="line.442"></a>
<FONT color="green">443</FONT>         *   &lt;/tr&gt;<a name="line.443"></a>
<FONT color="green">444</FONT>         *   &lt;tr&gt;<a name="line.444"></a>
<FONT color="green">445</FONT>         *     &lt;td valign=top&gt;<a name="line.445"></a>
<FONT color="green">446</FONT>         *       &lt;b&gt;Postcondition&lt;/b&gt;:<a name="line.446"></a>
<FONT color="green">447</FONT>         *     &lt;/td&gt;<a name="line.447"></a>
<FONT color="green">448</FONT>         *     &lt;td valign=top&gt;<a name="line.448"></a>
<FONT color="green">449</FONT>         *       result = value.hashCode()<a name="line.449"></a>
<FONT color="green">450</FONT>         *     &lt;/td&gt;<a name="line.450"></a>
<FONT color="green">451</FONT>         *     &lt;td valign=top&gt;<a name="line.451"></a>
<FONT color="green">452</FONT>         *     &lt;/td&gt;<a name="line.452"></a>
<FONT color="green">453</FONT>         *   &lt;/tr&gt;<a name="line.453"></a>
<FONT color="green">454</FONT>         * &lt;/table&gt;<a name="line.454"></a>
<FONT color="green">455</FONT>         *<a name="line.455"></a>
<FONT color="green">456</FONT>         * @return the hash Value<a name="line.456"></a>
<FONT color="green">457</FONT>         * @see &lt;a href="../../srchtml/lex/Token.html#hashCode"&gt;Source Code&lt;/a&gt;<a name="line.457"></a>
<FONT color="green">458</FONT>         */<a name="line.458"></a>
<FONT color="green">459</FONT>        public int hashCode()<a name="line.459"></a>
<FONT color="green">460</FONT>        {<a name="line.460"></a>
<FONT color="green">461</FONT>            return value.hashCode() + type.hashCode();<a name="line.461"></a>
<FONT color="green">462</FONT>        }<a name="line.462"></a>
<FONT color="green">463</FONT>    <a name="line.463"></a>
<FONT color="green">464</FONT>    //Auxillary Methods and Tokens<a name="line.464"></a>
<FONT color="green">465</FONT>        /**<a name="line.465"></a>
<FONT color="green">466</FONT>         * Checks the precondition of the non-copy constructors.  Since we only<a name="line.466"></a>
<FONT color="green">467</FONT>         * check preconditions, the only purpose of this method is to throw an<a name="line.467"></a>
<FONT color="green">468</FONT>         * exception if an error is found.  Otherwise it does nothing.<a name="line.468"></a>
<FONT color="green">469</FONT>         * <a name="line.469"></a>
<FONT color="green">470</FONT>         * &lt;p&gt;<a name="line.470"></a>
<FONT color="green">471</FONT>         * &lt;table&gt;<a name="line.471"></a>
<FONT color="green">472</FONT>         *   &lt;tr&gt;<a name="line.472"></a>
<FONT color="green">473</FONT>         *     &lt;td valign=top&gt;<a name="line.473"></a>
<FONT color="green">474</FONT>         *       &lt;b&gt;Precondition&lt;/b&gt;:<a name="line.474"></a>
<FONT color="green">475</FONT>         *     &lt;/td&gt;<a name="line.475"></a>
<FONT color="green">476</FONT>         *     &lt;td valign=top&gt;<a name="line.476"></a>
<FONT color="green">477</FONT>         *       type &amp;ne; null &lt;br/&gt;<a name="line.477"></a>
<FONT color="green">478</FONT>         *       lineNumber &amp;gt;= 1 &lt;br/&gt;<a name="line.478"></a>
<FONT color="green">479</FONT>         *       type &amp;ne; TokenType.EOF &amp;rArr; value &amp;ne; null &lt;br/&gt;<a name="line.479"></a>
<FONT color="green">480</FONT>         *       type &amp;ne; TokenType.EOF AND type &amp;ne; TokenType.STRING &amp;rArr;<a name="line.480"></a>
<FONT color="green">481</FONT>         *            |value| &amp;gt; 0 &lt;br/&gt;<a name="line.481"></a>
<FONT color="green">482</FONT>         *       type == TokenType.STRING &amp;rArr; (isLetter(value[0]) &lt;br/&gt;<a name="line.482"></a>
<FONT color="green">483</FONT>         *       &amp;forall;&lt;sub&gt;i&lt;/sub&gt; (0 &amp;lt;= i AND i &amp;lt; |value| &amp;rArr;<a name="line.483"></a>
<FONT color="green">484</FONT>         *           (isLetterOrDigit(value[i]))) &lt;br/&gt;<a name="line.484"></a>
<FONT color="green">485</FONT>         *       type == TokenType.SCHEMES &amp;rArr; value.equalsIgnoreCase(<a name="line.485"></a>
<FONT color="green">486</FONT>         *           "Schemes") &lt;br/&gt;<a name="line.486"></a>
<FONT color="green">487</FONT>         *       type == TokenType.Facts &amp;rArr; value.equalsIgnoreCase("Facts")&lt;br/&gt;<a name="line.487"></a>
<FONT color="green">488</FONT>         *       type == TokenType.Rules &amp;rArr; value.equalsIgnoreCase("Rules")&lt;br/&gt;<a name="line.488"></a>
<FONT color="green">489</FONT>         *       type == TokenType.Rules &amp;rArr; value.equalsIgnoreCase("Queries")<a name="line.489"></a>
<FONT color="green">490</FONT>         *           &lt;br/&gt;<a name="line.490"></a>
<FONT color="green">491</FONT>         *       type == TokenType.COLON_DASH &amp;rArr; value = ":-" &lt;br/&gt;<a name="line.491"></a>
<FONT color="green">492</FONT>         *       type == TokenType.COLON      &amp;rArr; value = ":"  &lt;br/&gt;<a name="line.492"></a>
<FONT color="green">493</FONT>         *       type == TokenType.COMMA      &amp;rArr; value = ","  &lt;br/&gt;<a name="line.493"></a>
<FONT color="green">494</FONT>         *       type == TokenType.PERIOD     &amp;rArr; value = "."  &lt;br/&gt;<a name="line.494"></a>
<FONT color="green">495</FONT>         *       type == TokenType.LEFT_PAREN &amp;rArr; value = "(" &lt;br/&gt;<a name="line.495"></a>
<FONT color="green">496</FONT>         *       type == TokenType.RIGHT_PAREN&amp;rArr; value = ")" &lt;br/&gt;<a name="line.496"></a>
<FONT color="green">497</FONT>         *       type == TokenType.Q_MARK     &amp;rArr; value = "?" &lt;br/&gt;<a name="line.497"></a>
<FONT color="green">498</FONT>         *       lineNumber &amp;gt;= 1<a name="line.498"></a>
<FONT color="green">499</FONT>         *     &lt;/td&gt;<a name="line.499"></a>
<FONT color="green">500</FONT>         *     &lt;td valign=top&gt;<a name="line.500"></a>
<FONT color="green">501</FONT>         *       AND&lt;br/&gt;<a name="line.501"></a>
<FONT color="green">502</FONT>         *       AND&lt;br/&gt;<a name="line.502"></a>
<FONT color="green">503</FONT>         *       AND&lt;br/&gt;<a name="line.503"></a>
<FONT color="green">504</FONT>         *       AND&lt;br/&gt;<a name="line.504"></a>
<FONT color="green">505</FONT>         *       AND&lt;br/&gt;<a name="line.505"></a>
<FONT color="green">506</FONT>         *       AND&lt;br/&gt;<a name="line.506"></a>
<FONT color="green">507</FONT>         *       AND&lt;br/&gt;<a name="line.507"></a>
<FONT color="green">508</FONT>         *       AND&lt;br/&gt;<a name="line.508"></a>
<FONT color="green">509</FONT>         *       AND&lt;br/&gt;<a name="line.509"></a>
<FONT color="green">510</FONT>         *       AND&lt;br/&gt;<a name="line.510"></a>
<FONT color="green">511</FONT>         *       AND&lt;br/&gt;<a name="line.511"></a>
<FONT color="green">512</FONT>         *       AND&lt;br/&gt;<a name="line.512"></a>
<FONT color="green">513</FONT>         *       AND&lt;br/&gt;<a name="line.513"></a>
<FONT color="green">514</FONT>         *       AND&lt;br/&gt;<a name="line.514"></a>
<FONT color="green">515</FONT>         *       AND&lt;br/&gt;<a name="line.515"></a>
<FONT color="green">516</FONT>         *       AND&lt;br/&gt;<a name="line.516"></a>
<FONT color="green">517</FONT>         *       AND&lt;br/&gt;<a name="line.517"></a>
<FONT color="green">518</FONT>         *       &amp;nbsp;<a name="line.518"></a>
<FONT color="green">519</FONT>         *     &lt;/td&gt;<a name="line.519"></a>
<FONT color="green">520</FONT>         *   &lt;/tr&gt;<a name="line.520"></a>
<FONT color="green">521</FONT>         *   &lt;tr&gt;<a name="line.521"></a>
<FONT color="green">522</FONT>         *     &lt;td valign=top&gt;<a name="line.522"></a>
<FONT color="green">523</FONT>         *       &lt;b&gt;PostCondition&lt;/b&gt;:<a name="line.523"></a>
<FONT color="green">524</FONT>         *     &lt;/td&gt;<a name="line.524"></a>
<FONT color="green">525</FONT>         *     &lt;td valign=top&gt;<a name="line.525"></a>
<FONT color="green">526</FONT>         *       true<a name="line.526"></a>
<FONT color="green">527</FONT>         *     &lt;/td&gt;<a name="line.527"></a>
<FONT color="green">528</FONT>         *     &lt;td valign=top&gt;<a name="line.528"></a>
<FONT color="green">529</FONT>         *     &lt;/td&gt;<a name="line.529"></a>
<FONT color="green">530</FONT>         *   &lt;/tr&gt;<a name="line.530"></a>
<FONT color="green">531</FONT>         *  <a name="line.531"></a>
<FONT color="green">532</FONT>         * &lt;/table&gt;<a name="line.532"></a>
<FONT color="green">533</FONT>         *<a name="line.533"></a>
<FONT color="green">534</FONT>         * @param type  the token type to be checked.<a name="line.534"></a>
<FONT color="green">535</FONT>         * @param value the value of the new token.<a name="line.535"></a>
<FONT color="green">536</FONT>         * @param lineNumber the lineNumber of the new token<a name="line.536"></a>
<FONT color="green">537</FONT>         *<a name="line.537"></a>
<FONT color="green">538</FONT>         * @throws ParserException<a name="line.538"></a>
<FONT color="green">539</FONT>         * @see &lt;a href="../../srchtml/lex/Token.html#constructorPrecond"&gt;Source Code&lt;/a&gt;<a name="line.539"></a>
<FONT color="green">540</FONT>         */<a name="line.540"></a>
<FONT color="green">541</FONT>        protected void checkConstructorPrecondition(<a name="line.541"></a>
<FONT color="green">542</FONT>            TokenType type, String value, int lineNumber)<a name="line.542"></a>
<FONT color="green">543</FONT>            throws ParserException<a name="line.543"></a>
<FONT color="green">544</FONT>        {<a name="line.544"></a>
<FONT color="green">545</FONT>            String errorMessage = null;<a name="line.545"></a>
<FONT color="green">546</FONT>            if(type == null){<a name="line.546"></a>
<FONT color="green">547</FONT>                errorMessage = "type cannot be null";<a name="line.547"></a>
<FONT color="green">548</FONT>            } else if(type != TokenType.EOF &amp;&amp; value == null){ <a name="line.548"></a>
<FONT color="green">549</FONT>                errorMessage = "type != TokenType.EOF =&gt; value != null";<a name="line.549"></a>
<FONT color="green">550</FONT>            } else if(type != TokenType.EOF &amp;&amp; type != TokenType.STRING &amp;&amp;<a name="line.550"></a>
<FONT color="green">551</FONT>                      value.length() == 0<a name="line.551"></a>
<FONT color="green">552</FONT>                     ){ <a name="line.552"></a>
<FONT color="green">553</FONT>                errorMessage = "If the token is not an EOF or String token " +<a name="line.553"></a>
<FONT color="green">554</FONT>                                "then |value| &gt; 0";<a name="line.554"></a>
<FONT color="green">555</FONT>            } else if(type == TokenType.ID &amp;&amp;<a name="line.555"></a>
<FONT color="green">556</FONT>                      !(Character.isLetter(value.charAt(0)) &amp;&amp;<a name="line.556"></a>
<FONT color="green">557</FONT>                        allTheRestMustBeLettersOrDigits(value))){<a name="line.557"></a>
<FONT color="green">558</FONT>                errorMessage = "type = TokenType.STRING =&gt;\n" +<a name="line.558"></a>
<FONT color="green">559</FONT>                                "    the first character in value must be a letter"+<a name="line.559"></a>
<FONT color="green">560</FONT>                                " and\n" +<a name="line.560"></a>
<FONT color="green">561</FONT>                                "    the rest must be letters or digits";<a name="line.561"></a>
<FONT color="green">562</FONT>            } else if(type == TokenType.SCHEMES &amp;&amp;<a name="line.562"></a>
<FONT color="green">563</FONT>                      !value.equalsIgnoreCase("Schemes")){<a name="line.563"></a>
<FONT color="green">564</FONT>                errorMessage = "type = TokenType.SCHEMES =&gt;\n" +<a name="line.564"></a>
<FONT color="green">565</FONT>                                "    value.equalsIgnoreCase(\"Schemes\")";<a name="line.565"></a>
<FONT color="green">566</FONT>            } else if(type == TokenType.FACTS &amp;&amp;<a name="line.566"></a>
<FONT color="green">567</FONT>                      !value.equalsIgnoreCase("Facts")){ <a name="line.567"></a>
<FONT color="green">568</FONT>                errorMessage = "type = TokenType.FACTS =&gt;\n" +<a name="line.568"></a>
<FONT color="green">569</FONT>                                "    value.equalsIgnoreCase(\"Facts\")";<a name="line.569"></a>
<FONT color="green">570</FONT>            } else if(type == TokenType.RULES &amp;&amp;<a name="line.570"></a>
<FONT color="green">571</FONT>                      !value.equalsIgnoreCase("Rules")){ <a name="line.571"></a>
<FONT color="green">572</FONT>                errorMessage = "type = TokenType.RULES =&gt;\n" +<a name="line.572"></a>
<FONT color="green">573</FONT>                                "    value.equalsIgnoreCase(\"Rules\")";<a name="line.573"></a>
<FONT color="green">574</FONT>            } else if(type == TokenType.QUERIES &amp;&amp;<a name="line.574"></a>
<FONT color="green">575</FONT>                      !value.equalsIgnoreCase("Queries")){ <a name="line.575"></a>
<FONT color="green">576</FONT>                errorMessage = "type = TokenType.QUERIES =&gt;\n" +<a name="line.576"></a>
<FONT color="green">577</FONT>                                "    value.equalsIgnoreCase(\"Queries\")";<a name="line.577"></a>
<FONT color="green">578</FONT>            } else if(type == TokenType.COLON_DASH &amp;&amp; !value.equals(":-")){<a name="line.578"></a>
<FONT color="green">579</FONT>                errorMessage = "type = TokenType.COLON_DASH =&gt; value = \":-\""; <a name="line.579"></a>
<FONT color="green">580</FONT>            } else if(type == TokenType.COLON &amp;&amp; !value.equals(":")){<a name="line.580"></a>
<FONT color="green">581</FONT>                errorMessage = "type = TokenType.COLON =&gt; value = \":\""; <a name="line.581"></a>
<FONT color="green">582</FONT>            } else if(type == TokenType.COMMA &amp;&amp; !value.equals(",")){<a name="line.582"></a>
<FONT color="green">583</FONT>                errorMessage = "type = TokenType.COMMA =&gt; value = \",\""; <a name="line.583"></a>
<FONT color="green">584</FONT>            } else if(type == TokenType.PERIOD &amp;&amp; !value.equals(".")){<a name="line.584"></a>
<FONT color="green">585</FONT>                errorMessage = "type = TokenType.PERIOD =&gt; value = \".\""; <a name="line.585"></a>
<FONT color="green">586</FONT>            } else if(type == TokenType.LEFT_PAREN &amp;&amp; !value.equals("(")){<a name="line.586"></a>
<FONT color="green">587</FONT>                errorMessage = "type = TokenType.LEFT_PAREN =&gt; value = \"(\""; <a name="line.587"></a>
<FONT color="green">588</FONT>            } else if(type == TokenType.RIGHT_PAREN &amp;&amp; !value.equals(")")){<a name="line.588"></a>
<FONT color="green">589</FONT>                errorMessage = "type = TokenType.RIGHT_PAREN =&gt; value = \")\""; <a name="line.589"></a>
<FONT color="green">590</FONT>            } else if(type == TokenType.Q_MARK &amp;&amp; !value.equals("?")){<a name="line.590"></a>
<FONT color="green">591</FONT>                errorMessage = "type = TokenType.Q_MARK =&gt; value = \"?\""; <a name="line.591"></a>
<FONT color="green">592</FONT>            } else if(lineNumber &lt;= 0){<a name="line.592"></a>
<FONT color="green">593</FONT>                errorMessage = "lineNumber must be &gt;= 1";<a name="line.593"></a>
<FONT color="green">594</FONT>            };<a name="line.594"></a>
<FONT color="green">595</FONT>            if(errorMessage != null)<a name="line.595"></a>
<FONT color="green">596</FONT>                throw new ParserException(<a name="line.596"></a>
<FONT color="green">597</FONT>                   "ERROR in one of the Token::constructor\n" + errorMessage);<a name="line.597"></a>
<FONT color="green">598</FONT>        }<a name="line.598"></a>
<FONT color="green">599</FONT>    <a name="line.599"></a>
<FONT color="green">600</FONT>        /**<a name="line.600"></a>
<FONT color="green">601</FONT>         * Returns true if value[1..|value|-1] are all letters or digits, otherwise<a name="line.601"></a>
<FONT color="green">602</FONT>         * it returns false.<a name="line.602"></a>
<FONT color="green">603</FONT>         *<a name="line.603"></a>
<FONT color="green">604</FONT>         * &lt;p&gt;<a name="line.604"></a>
<FONT color="green">605</FONT>         * &lt;table&gt;<a name="line.605"></a>
<FONT color="green">606</FONT>         *   &lt;tr&gt;<a name="line.606"></a>
<FONT color="green">607</FONT>         *     &lt;td valign=top&gt;<a name="line.607"></a>
<FONT color="green">608</FONT>         *       &lt;b&gt;Precondition&lt;/b&gt;:<a name="line.608"></a>
<FONT color="green">609</FONT>         *     &lt;/td&gt;<a name="line.609"></a>
<FONT color="green">610</FONT>         *     &lt;td valign=top&gt;<a name="line.610"></a>
<FONT color="green">611</FONT>         *       none<a name="line.611"></a>
<FONT color="green">612</FONT>         *     &lt;/td&gt;<a name="line.612"></a>
<FONT color="green">613</FONT>         *     &lt;td valign=top&gt;<a name="line.613"></a>
<FONT color="green">614</FONT>         *     &lt;/td&gt;<a name="line.614"></a>
<FONT color="green">615</FONT>         *   &lt;/tr&gt;<a name="line.615"></a>
<FONT color="green">616</FONT>         *   &lt;tr&gt;<a name="line.616"></a>
<FONT color="green">617</FONT>         *     &lt;td valign=top&gt;<a name="line.617"></a>
<FONT color="green">618</FONT>         *       &lt;b&gt;Postcondition&lt;/b&gt;:<a name="line.618"></a>
<FONT color="green">619</FONT>         *     &lt;/td&gt;<a name="line.619"></a>
<FONT color="green">620</FONT>         *     &lt;td valign=top&gt;<a name="line.620"></a>
<FONT color="green">621</FONT>         *       result = value &amp;ne; null &lt;br/&gt;<a name="line.621"></a>
<FONT color="green">622</FONT>         *       &amp;forall;&lt;sub&gt;i&lt;/sub&gt; (0 &amp;lt; i AND i &amp;lt; |value| &amp;rArr;<a name="line.622"></a>
<FONT color="green">623</FONT>         *           isLetterOrDigit(str[i]))<a name="line.623"></a>
<FONT color="green">624</FONT>         *     &lt;/td&gt;<a name="line.624"></a>
<FONT color="green">625</FONT>         *     &lt;td valign=top&gt;<a name="line.625"></a>
<FONT color="green">626</FONT>         *       AND &lt;br/&gt;<a name="line.626"></a>
<FONT color="green">627</FONT>         *       &amp;nbsp;<a name="line.627"></a>
<FONT color="green">628</FONT>         *     &lt;/td&gt;<a name="line.628"></a>
<FONT color="green">629</FONT>         *   &lt;/tr&gt;<a name="line.629"></a>
<FONT color="green">630</FONT>         * &lt;/table&gt;<a name="line.630"></a>
<FONT color="green">631</FONT>         *<a name="line.631"></a>
<FONT color="green">632</FONT>         * @param value the string to be inspected.<a name="line.632"></a>
<FONT color="green">633</FONT>         *<a name="line.633"></a>
<FONT color="green">634</FONT>         * @return whether or not all but the first character are letters and<a name="line.634"></a>
<FONT color="green">635</FONT>         *         digits.<a name="line.635"></a>
<FONT color="green">636</FONT>         * @see &lt;a href="../../srchtml/lex/Token.html#lettersOrDigits"&gt;Source Code&lt;/a&gt;<a name="line.636"></a>
<FONT color="green">637</FONT>         */<a name="line.637"></a>
<FONT color="green">638</FONT>        protected boolean allTheRestMustBeLettersOrDigits(String value)<a name="line.638"></a>
<FONT color="green">639</FONT>        {<a name="line.639"></a>
<FONT color="green">640</FONT>            boolean result = value != null;<a name="line.640"></a>
<FONT color="green">641</FONT>    <a name="line.641"></a>
<FONT color="green">642</FONT>            for(int i = 1; result &amp;&amp; i &lt; value.length(); i++){<a name="line.642"></a>
<FONT color="green">643</FONT>                result = Character.isLetterOrDigit(value.charAt(i));<a name="line.643"></a>
<FONT color="green">644</FONT>            };<a name="line.644"></a>
<FONT color="green">645</FONT>    <a name="line.645"></a>
<FONT color="green">646</FONT>            return result;<a name="line.646"></a>
<FONT color="green">647</FONT>        }<a name="line.647"></a>
<FONT color="green">648</FONT>    }<a name="line.648"></a>




























































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